1. Field of the Invention
The present invention relates to a valve train for an internal combustion engine in which an opening and closing timing and a maximum lift amount of an engine valve, which is a inlet valve or an exhaust valve, can be changed.
2. Description of the Related Art
For an example, Japanese Patent Unexamined Publication JP-A-7-63023 shows a valve train. The valve train includes: a transmission member having a supporting point moved by a rotatable eccentric body so that a reciprocating motion of a reciprocating valve on the suction side provided in the cylinder head can be adjusted, the transmission member opening and closing the reciprocating valve being driven by a cam of a cam shaft; and a swing lever for opening and closing a reciprocating valve on the exhaust side. An eccentric shaft on which the eccentric body is formed is arranged in an upper portion of the swing lever provided for the reciprocating valves on the suction and the exhaust side.
In this connection, in the valve train of the JP-A-7-63023, the eccentric shaft is arranged far from the reference plane, which is a plane including the cylinder axis and arranged in parallel with the rotational center axis of the cam, relative to the suction side reciprocating valve. Therefore, in the reference direction, which is a direction perpendicular to the reference plane, the valve train is made larger. Since the eccentric shaft is arranged in an upper portion of the exhaust side reciprocating valve, the valve train is made larger in the vertical direction.